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author | Paul Phillips <paulp@improving.org> | 2012-03-20 20:15:45 -0700 |
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committer | Paul Phillips <paulp@improving.org> | 2012-03-20 20:15:45 -0700 |
commit | fcc63e2b667bdbaddbaacc843de97f8db02f6426 (patch) | |
tree | 9ee7bd6e4cb9e487a0d5c5b9c812a68c4c0ed025 /src | |
parent | 1c65152c7aaeb3aeaf8a5e39e6fd51e5b4b95836 (diff) | |
download | scala-fcc63e2b667bdbaddbaacc843de97f8db02f6426.tar.gz scala-fcc63e2b667bdbaddbaacc843de97f8db02f6426.tar.bz2 scala-fcc63e2b667bdbaddbaacc843de97f8db02f6426.zip |
Restore irrefutability commits.
This reverts commit d8ba5d091e5641553b438ef9930a6023a2709dcd.
Diffstat (limited to 'src')
3 files changed, 35 insertions, 21 deletions
diff --git a/src/compiler/scala/reflect/internal/TreeInfo.scala b/src/compiler/scala/reflect/internal/TreeInfo.scala index 769d7a9ed1..ce3de94335 100644 --- a/src/compiler/scala/reflect/internal/TreeInfo.scala +++ b/src/compiler/scala/reflect/internal/TreeInfo.scala @@ -17,7 +17,7 @@ abstract class TreeInfo { val global: SymbolTable import global._ - import definitions.{ isVarArgsList, isCastSymbol, ThrowableClass } + import definitions.{ isVarArgsList, isCastSymbol, ThrowableClass, TupleClass } /* Does not seem to be used. Not sure what it does anyway. def isOwnerDefinition(tree: Tree): Boolean = tree match { @@ -312,6 +312,24 @@ abstract class TreeInfo { case _ => false } + /** Is this tree comprised of nothing but identifiers, + * but possibly in bindings or tuples? For instance + * + * foo @ (bar, (baz, quux)) + * + * is a variable pattern; if the structure matches, + * then the remainder is inevitable. + */ + def isVariablePattern(tree: Tree): Boolean = tree match { + case Bind(name, pat) => isVariablePattern(pat) + case Ident(name) => true + case Apply(sel, args) => + ( isReferenceToScalaMember(sel, TupleClass(args.size).name.toTermName) + && (args forall isVariablePattern) + ) + case _ => false + } + /** Is this argument node of the form <expr> : _* ? */ def isWildcardStarArg(tree: Tree): Boolean = tree match { diff --git a/src/compiler/scala/tools/nsc/ast/parser/TreeBuilder.scala b/src/compiler/scala/tools/nsc/ast/parser/TreeBuilder.scala index 0d2fbc5372..0bc88d1efd 100644 --- a/src/compiler/scala/tools/nsc/ast/parser/TreeBuilder.scala +++ b/src/compiler/scala/tools/nsc/ast/parser/TreeBuilder.scala @@ -262,29 +262,25 @@ abstract class TreeBuilder { else if (stats.length == 1) stats.head else Block(stats.init, stats.last) + def makeFilter(tree: Tree, condition: Tree, scrutineeName: String): Tree = { + val cases = List( + CaseDef(condition, EmptyTree, Literal(Constant(true))), + CaseDef(Ident(nme.WILDCARD), EmptyTree, Literal(Constant(false))) + ) + val matchTree = makeVisitor(cases, false, scrutineeName) + + atPos(tree.pos)(Apply(Select(tree, nme.withFilter), matchTree :: Nil)) + } + /** Create tree for for-comprehension generator <val pat0 <- rhs0> */ def makeGenerator(pos: Position, pat: Tree, valeq: Boolean, rhs: Tree): Enumerator = { val pat1 = patvarTransformer.transform(pat) val rhs1 = - if (valeq) rhs - else matchVarPattern(pat1) match { - case Some(_) => - rhs - case None => - atPos(rhs.pos) { - Apply( - Select(rhs, nme.filter), - List( - makeVisitor( - List( - CaseDef(pat1.duplicate, EmptyTree, Literal(Constant(true))), - CaseDef(Ident(nme.WILDCARD), EmptyTree, Literal(Constant(false)))), - false, - nme.CHECK_IF_REFUTABLE_STRING - ))) - } - } - if (valeq) ValEq(pos, pat1, rhs1) else ValFrom(pos, pat1, rhs1) + if (valeq || treeInfo.isVariablePattern(pat)) rhs + else makeFilter(rhs, pat1.duplicate, nme.CHECK_IF_REFUTABLE_STRING) + + if (valeq) ValEq(pos, pat1, rhs1) + else ValFrom(pos, pat1, rhs1) } def makeParam(pname: TermName, tpe: Tree) = diff --git a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala index fa19f380fd..d98d248231 100644 --- a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala +++ b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala @@ -1445,7 +1445,7 @@ abstract class RefChecks extends InfoTransform with reflect.internal.transform.R private def transformApply(tree: Apply): Tree = tree match { case Apply( - Select(qual, nme.filter), + Select(qual, nme.filter | nme.withFilter), List(Function( List(ValDef(_, pname, tpt, _)), Match(_, CaseDef(pat1, _, _) :: _)))) |